The present invention relates to a scanning apparatus and, particularly, to such an apparatus for scanning a stimulable phosphor which has been exposed imagewise to light, radiation or an electron beam and stores the energy of light, radiation or an electron beam in the form of an image with an electromagnetic wave to stimulate it, thereby causing it to emit the energy of the light, radiation or an electron beam in the form of image-bearing light, and photoelectrically detecting emitted light, thereby reading the image of light, radiation or an electron beam stored in the stimulable phosphor at high density and without producing any wave-like unevenness in the image.